Iprovement in thrashing-machines



JOHN RUMBLY, 0F LA PORTE, NDIANA.

lNlRl/EMNT iN THRASHlNG-MACHINES.

Specification forming part of Letters Patent No. i, dared .-lpril 1879: application tiled September i9, 1878.

To all 107mm 'if may concern.:

Be it known that I, JOHN Rmrnnr, of La Porte, in the county of La Porte and State of indiana, have invented certain new and use' ful improvements in Thrashing-Machines; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being made to the accompanying drawings, which form a part ot' this specilication, in which- Figure l is a side view of a cylinder for a thrashing-niachiiie embodying my improvement. Big. 2 is a similar view of the concave; Fig. 3, a sectional View et' one of the longi tudinal teethsupporting ribs of the cylinder or concave, showing one ot' the teeth and its .method of attachment. Fig. fl is a side view of one ot" said ribs, showing two teeth. Fig. 5 is a sectional diagram to illustrate the pur )ose ci making the teeth rounded at the sides.

Like letters oi' reference denote like parts wherever employed in the several gures.

in the said drawings, A A, Sie., represent the longitudinal metal hars of the cylinder or concave. l usually employ twelve of these ribs upon a cylinder, and they are supported, as shown at Fig. l, from a circular framework of suitable structure, such as is ordi narily employed in thrashing-machine cylinders of the present day. B B are the teeth, made with a shank, b, which fits into a square hole in the bar, and is provided with a round extension, bl, out with a thread, to receive a nut, b2.

When all of the teeth for a single bar are inserted a wooden strip, made preferably of hard wood, as shown at C, is applied to the under or hat side of the bar, and, being perforated at suitable points for the extensions or Shanks b1 to pass through it, is pressed up against the bar. A Washer, b3, may then be applied, and the nuts b2 screwed imly down to set the teeth securely to the bar. rlhis produces a very tight and lasting means foi; securing the teeth in place.

yields just enough to canse a rigid lock to be effected, and the teeth cannot rattle loose thereafter.

The teeth are made of the ordinaryform,

The wooden strip l broadening from their insertion to the outer extremity, and at the same time becoming thinner.

The chiefdierence between my improved teeth and former teeth consists in the fact that my improved teeth are made oval in cross-section-that is to say, the two sides of the tooth are rounded, as shown in crosssection at Fig. 5.

It will be understood that the strength and durability of the teeth are greatly enhanced by reason of the form given them. I do not now refer to the oval character of the crosssection, but to the fact oi' their being broadened and attened from their insertion toward the outer extremity.

In making cylinders and concayes it is the intention to set the teeth perfectly true, so that as the teeih of the cylinder pass those of the concave the space between the opposing teeth shall always be true and equal from end to end without variation; but it is not always possible to do this perfectly by reason of the flattened shape of the tooth, which exaggerates any niisplaecnient, and if done per fectly at rst it may happen that a tooth may become bent or turned slightly'.

The difficulty occasioned by bending is not easy to remedy, except by removal and renewal ot the tooth. The rounding of sides ot' the tooth will, however, compensate for any accidental displacement by turning. Moreover, it will enable the cylinder to be construeted with greater ease, as such great pains or accuracy in setting the teeth will not be necessary.

This will be understood from the diagram at Fig. 5. It will be noticed in that ligure that the left-hand tooth is straight with the paper, while the right-hand one is turned or rotated slightly to an incline. Still it will be observed that the space between the teeth has not either increased or diminished by reason of this rotation.

It may be remarked for the benet oi' those not skilled in such matters that the reason it is necessary to have the space between the teeth always thersamc, and the teeth truly aligned, is because otherwise a wedging'ac. tion of the straw between the teeth is liable to take. piave. '.llu,l rounding;l if tlm ilzil lvch l The improieil moth for thrashing-maclninc makes them selfzuljmtml without slwvinl afcylinders und concaves, the said tooth being Lentjon tn this point. willem-l and flattened fmmitsnscrtinn toward I am aware that, round Winti-l pegs hav@ irsouterextreiuity,and huvingthesides roundbeen used for teeth, and I do nm claim such ed, substantially :is :md for the purpose specias m5 invention, because, ulrlmugli ac vlindrilied.

cul peg cannot, of course, gut out of' alignment,

by turning, Still it is not a desirable form, not,

being so strong or effective as the flattenvd Witnesses:

tooth. Il. l-IANsnEnR,

I claim- G Eo. C. lYnmLAND.

JOHN RUMELY. 

